Load bearing safety belt buckle construction

ABSTRACT

A safety belt buckle assembly has a tongue plate attached to one belt section matingly engaging a buckle attached to another belt section, where the buckle includes a non-structural housing surrounding a through-load member and a push button operated latch assembly for selectively coupling tension loads between the through-load member and the tongue plate such that the housing itself serves merely as an encapsulating member. The through-load member in addition to carrying the tension loads is provided with improved bending load retaining means for bearing bending loads in the buckle between the through-load member and the tongue plate.

United States Patent [191 Tanaka Nov. 25, 1975 [75] Inventor: Akira Tanaka, Northridge, Calif.

[73] Assignee: American Safety Equipment Corporation, Encino, Calif.

[22] Filed: Feb. 26, 1974 [21] Appl. No.: 445,838

[52] U.S. Cl 24/230 A [51] Int. Cl. A44B 11/26 [58] Field of Search 24/230 A [56] References Cited UNITED STATES PATENTS 3,137,907 6/1964 Unai 24/230 A 3,170,211 2/1965 Van Noord A 24/230 A 3,246,377 4/1966 Brown 24/230 A 3,343,228 9/1967 Close 4. 24/230 A 3,491,415 l/l970 Hughesum 24/230 A 3,686,720 8/1972 Wehner 24/23(] A 3,790,994 2/1974 Jakob v 24/230 A 3,795,030 3/1974 Yates 24/230 AL FOREIGN PATENTS OR APPLICATIONS 988,478 4/1965 United Kingdom 24/230 A Primary Examiner-Bernard A. Gelak [57] ABSTRACT A safety belt buckle assembly has a tongue plate attached to one belt section matingly engaging a buckle attached to another belt section, where the buckle includes a non-structural housing surrounding a through-load member and a push button operated latch assembly for selectively coupling tension loads between the through-load member and the tongue plate such that the housing itself serves merely as an encapsulating member. The through-load member in addition to carrying the tension loads is provided with improved bending load retaining means for bearing bending loads in the buckle between the through-load member and the tongue plate.

1 Claim, 3 Drawing Figures U.S. Patent Nov. 25, 1975 Sheet 1 of 3 3,921,262

U.S. Patent Nov. 25, 1975 Sheet20f3 3,921,262

U.S. Patent Nov. 25, 1975 Sheet 3 013 3,921,262

BACKGROUND OF THE INVENTION The present invention relates in general to safety belt buckles of the type wherein a tongue plate is received and releasably held within a non-load bearing buckle housing by engagement with a through-load receiving member and an interengaging latch member. More specifically, the present invention relates to an improvement in the through-load bearing member of the safety belt buckle of the prior U.S. Pat. No. 3,790,994.

In the buckle of the prior U.S. Pat. No. 3,790,994, an apertured tongue plate attached to one strap or belt section is matingly engaged and releasably retained by a buckle member attached to a second strap or belt section. The buckle of said patent includes a non-structural housing surrounding a through-load member which is adapted to be connected at an end thereof to one of the safety straps. A latch member is pivotally mounted to the through-load member and operated by an associated push button release member for disengaging a tongue plate coupled to the through-load member by the aforementioned latch member.

The through-load member of the aforesaid U.S. Pat. No. 3,790,994 was provided with guide means adjacent a forward portion of the through-load member for guiding a tongue plate received for engagement therewith. In addition, tabs integrally formed of the through-load member were provided for overlying portions of the tongue plate to receive transverse loads imparted between the tongue plate and through-load member, as when a bending load was placed upon the assembled buckle and tongue plate assembly. While this arrangement has been generally satisfactory, it has been found that an improved construction of through-load member, specifically with regard to the means for receiving bending loads imparted thereon from the tongue plate, is a desideratum in the art of safety belt buckles.

It is therefore an object of the present invention to disclose and provide an improvement in a safety belt buckle of the type hereinbefore described and in particular where the through-load member thereof has improved load bearing characteristics for the buckle when the assembled buckle and tongue plate are placed under bending loads, i.e. loading transverse to the plane in which the normal tensioning loads between the tongue plate and load bearing member occur.

These and other additional objects, as well as various advantages, of the present invention will become apparent to those skilled in the art from a consideration of the following description of a preferred exemplary embodiment of the improved load bearing safety belt buckle construction of the present invention.

Reference will be made to the appended sheets of drawings which will now be first described briefly.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a plan view of the push button type buckle of the type in which the present improved load bearing safety belt buckle construction is incorporated, in combination with a system of safety straps an co-operating tongue plate;

FIG. 2 is a section view of the tongue plate and buckle assembly of FIG. 1 taken therein along the plane llll;

FIGS. 3 and 4 are section views taken generally along the plane llll of FIG. I showing the tongue plate and buckle parts in FIG. 3 during insertion or release ofthe tongue plate and in FIG. 4 in an assembled matingly engaged relationship; and

FIG. 5 is an exploded perspective view of the exem plary safety belt buckle construction of FIGS. I through 4 showing the various elements thereof in a pre-assembled relationship.

DESCRIPTION OF THE PREFERRED EMBODIMENT a. The Environment of the Invention Referring to FIGS. 1, 2 and 5, it may be seen that the exemplary push button buckle 10, generally as in the prior U.S. Pat. No. 3,790.994, receives a tongue plate ll wherein both the tongue plate II and buckle I0 are adapted to be attached to safety strap sections l2, l3 and 14. In this manner the buckle provides releasable coupling of a lap strap 14 jointly to a lap strap 12 and shoulder strap I3 secured to the tongue plate 11. Buckle 10 comprises a non-structural housing 16 preferably formed of a light weight plastic material having some degree of resiliency, a load member indicated generally at 17 carried in housing 16 and serving to bear the entire load existing between tongue plate 11 and strap I4 such that none of the applied load force passes through the housing 16 itself. A latch member separate from load member 17, is disposed within the housing 16 and is movable relative to said load member 17. In addition to the load bearing function of load member 17, member 17 may also provide a mounting support for carrying the movable latch member for selective releasable engagement with an aperture 18 of tongue plate 11, wherein the latch member includes a latch plate 19 having a raised catch portion 2!. As more fully described herein. latch plate I9 is mounted in a generally underlying relationship to load member I7 and is hingedly supported thereby for movement between a latching position and a release position relative to aperture 18 of tongue plate II. A leaf spring member 22 serves as a biasing means for urging latch plate 19 into its latching position shown in FIG. 5 and a push button 23 also carried and supported by load member 17 functions to selectively manually move latch plate 19 away from load member 17 against spring member 22 toward a release position as shown by FIG. 4. To guide tongue plate 11 into and out of the buckle and restrain it in a plane overlying member 17, the load member is formed with integral guide and restraint means indicated at 20.

Now with specific reference to FIGS. 2 and 5. load member 17 is formed with a generally planar body including a catch guiding opening 26 therein shaped to matingly receive and guide raised catch portion 21 of latch plate 19. Plate 19 is disposed in a generally underlying relationship with load member 17 so that catch portion 21 protrudes through aperture 26 and in the latched condition extends above a tongue plate receiving surface 27 of member 17. To provide for articulation of latch plate 19 between its latched and released positions, it is hingedly supported by an integral tab 28 of member 17 bent to extend beneath opening 26 from an edge thereof adjacent a forward edge 29 of member 17 as best illustrated by FIG. 3. A recess 3] formed by and thus underlying raised catch portion 21 of latch plate 19 rests on and is supported by tab 28 such that the generally planar portion of latch plate 19 underlies member 17 and the entire plate is pivotally supported about an edge 32 of recess 31. Catch portion 21 may be thus moved to a latching position by pivoting plate 19 upwardly against the underside of member 17.

As seen in FIG. 5, raised catch portion 21 is provided with a camming surface 33 sloping upwardly away from edge 32 of recess 31 and terminating at a catch abutment 34 generally at right angles to camming surface 33 for engaging an abutment surface 36 of aperture 18 in tongue plate 11 (See FIG. 4). Camming surface 33 serves to allow a leading edge of tongue plate 11 upon entry into the buckle to force raised catch portion 21 of latch plate 19 downwardly to a position flush with surface 27 of member 17 (See FIG. 3). Abutment 34 of catch portion 21 has a slight bevel 35 on an upper edge thereof to facilitate release from tongue plate 11.

To transmit the force carried by catch abutment 34 of catch portion 21 to load member 17 when tongue plate 11 is in a latched condition as illustrated in FIG. 4, raised catch portion 21 is provided with abutment surfaces 37 opposite from catch abutment 34 and adjacent lateral edges of recess 31 for matingly engaging shoulders 38 of load member 17 defined by opening 26 adjacent each side of tab 28. In this manner tension loads are directly and positively transmitted from abutment surface 36 of tongue plate 11 to shoulders 38 of load members 17 by movable and low inertia latch plate 19.

Tongue plate guide means are provided in the form of integral upturned flanges 42 and 42 for laterally guiding and restraining tongue plate 11 as it is received on through-load member 17. Flanges 42 and 42' are disposed along opposite lateral edges of member 17 and adjacent its longitudinally forward edge as illustrated. Furthermore. the flanges 42, 42' are provided with a pair of longitudinally spaced apart integral tabs 43, 43' with end portions 51, 51 respectively turned laterally inwardly so as to provide additional guide sur faces overlying and vertically spaced from the leading edge of plate 11. A stop 50 may be provided to stop insertion of 43, 43' to provide for manual selective release of tongue plate 11 from a latched condition in the exemplary embodiment. The latch member is responsive to a push button 23 carried by load member 17 for pivotal movement about a pair of spaced coaxial arms 61 and 62 supported in a pair of cooperating bearing surfaces 63 and 63' formed in opposing flanges ears 42 and 42 of load member 17, and thus providing means for pivotally carrying the push button. The button may also be pivotally mounted in the sidewalls of the housing 16. Button 23 fixedly carries a lever extension 66, in this instance integral with the button. which in the as sembled position as shown in FIG. 4 extends through an access opening 67 in member 17 to and for engaging a surface abutment 68 of latch plate 19 spaced from pivot edge 32 of catch portion 21 so as to provide a moment of force on plate 19 about the pivotal axis thereof. ln this manner button 23 is supported by member 17 in a position overlying tongue plate receiving surface 27 and as best illustrated in FIG. 4 is responsive to a manual actuation force to pivot about arms 61 and 62 causing extension 66 to depress abutment 68 of latch plate 19 away from member 17 which in turn moves raised catch portion 21 from a latching position to a release position flush with surface 27 as seen in FIG. 3. Operating against extension 66 and push button 23, an upwardly sloping centrally located leaf 71 of spring biasing member 22 engages a surface of latch plate 19 op posite surface abutment 68 resiliently urging plate 19 toward load member 17. in its biased state latch plate 19 is urged against an under surface of member 17 and thus this under surface serves as a stop to further upward movement of raised catch portion 21. This condi tion is illustrated by FIGS. 2 and 4.

In its preferred form housing 16 of the buckle is formed in two parts, a base part 16a and a cover part 16b. Load member 17, the latch plate 19, spring mem ber 22 and push button 23 are all cooperatively formed so as to allow for unidirectional assembly into housing base part 160 for economical mass manufacture.

In particular base part 16a is formed with a cavity 72 and a tongue plate receiving opening 73 extending through an endwall thereof. Cavity 72 is shaped to receive in succession spring biasing member 22 with leaf 71 sloping upwardly away from opening 73, load mem ber 17 with latch plate 19 hingedly supported on tab 28 with the guide entry formed by ears 41 and 42 of member 17 communicating with housing opening 73 and opposite lateral edges of the under surface of member 17 resting on shoulders 74 defined in the housing cavity. An end of load member 17 opposite forward edge 29 rests on a shoulder 76 of base part 16a and lip 77 thereof resiliently retains this end of member 17. Push button 23 is received next with extension 66 passed downwardly through opening 67 and push button pivot arms 61 and 62 resting in bearing surfaces 63 and 64 of member 17. Finally, a housing cover provided by part 16b. having a push button access aperture 78, is mounted in place and secured to housing base part 16a by a forward and a pair of lateral resilient retaining tabs 81, 82 and 83 respectively, engaging cooperating shoulders 86, 87 and 88 respectively, formed in part 16a as best illustrated in FIGS. 2 and 3. A lower circumferential edge 89 of cover part 16b rests on an upper circumferential shoulder 90 of part 1611. As indicated above, housing 16 is formed of a plastic having a slight resiliency, such that tabs 81, 82 and 83 undergo some deformation during assembly of housing cover part 16b.

Cover part 1610 retains push button 23 by a circumferential stop surface surrounding aperture 78 and cooperating with an upper surface 91 of push button 23 surrounding a raised portion 92 which extends upwardly into aperture 78 of the housing cover. Accordingly. all of the foregoing components may be vertically dropped into housing base part 16a in a unidirectional assembly operation with housing cover part 16b being snapped in place to encapsulate the various parts within the plastic housing.

Housing base part and housing cover part 16b are formed with transversely registering openings 93 and 94 adjacent ends thereof opposite tongue plate receiving opening 73 for access to a strap receiving aperture 96 formed in load member 17. It is observed that all of the load placed on buckle 10 by strap 14 is carried by an edge of aperture 96 of load member 17 and not by any of the surrounding portions of housing 16.

In order to disassembly buckle 10, housing cover 16 may be released from base part 16a by inserting a slender tool, such as a screwdriver, under the corners of housing cover aperture 78 adjacent tabs 82 and releasing these tabs by lever tool action.

b. The Improvement The safety belt buckle construction and operation thus far discussed is essentially that of the prior U.S. Pat. No. 3,790,994. The insertion of the tongue plate into the buckle, and in particular the through-load member indicated generally at 17, is facilitated by the provision of the side flanges or ears 42, 42' and inwardly extending tabs 43, 43 as previously discussed. It has been found that in order to provide improved bending load receiving and anchoring means for the fully inserted tongue plate that such anchoring means be provided more inwardly of the through-load member, on opposite sides thereof, with a pair of spaced anchor means being provided for each side of the tongue plate.

Referring first to FIG. 5, it can be seen in the preferred exemplary embodiment that a pair of spaced upstanding anchor plate means are provided on each of two opposite sides of the through-load member by the forward flanges 42, 42' and rearward or inwardly spaced flanges 44, 44', all being integral of throughload member 17. These fairly widely spaced flanges or anchor plates are each interconnected by tongue plate anchoring means comprising, in the exemplary embodiment, a bar like member extending between each pair of spaced flanges 42, 44 and 42', 44', respectively. Preferably, and as illustrated in FIG. 5, each anchor bar includes side portions 46, 47 and 46', 4 7, respectively, which convergingly extend inwardly of through-load member from the associated flanges until they merge into a central portion 45, 45', respectively, which extends substantially parallel to the anchor plates or flanges 42, 44 and 42, 44', respectively. This construction places the central portions of the two anchor bars over marginal side portions of the tongue plate adjacent its leading edge upon insertion into the buckle, as best seen in FIG. 4, such that bending loads applied between the buckle and tongue plate will be received by the thus described tongue plate anchoring means. Such loading received by each of the tongue plate anchoring means is distributed in generally opposite directions through both of the associated upstanding anchor plate means or flanges to the through-load member in a manner which provides for a very high bending load accommodating buckle construction.

I claim:

1. In a safety buckle for receiving and engaging a tongue plate, the buckle including a non-load bearing housing surrounding a through-load member adapted to be connected at one end to a safety belt strap and having a latch member movable relative to the member for releasably engaging the tongue plate to the member, the member having a base plate and restraint means for laterally and transversely restraining the tongue plate in a plane adjacent and overlying the member base plate, the improvement in through-load member and its associated restraint means comprising the provision of:

guide means on said through-load member including opposed side wall flanges on said base plate forming a channel for receiving said tongue plate. each including portions extending into said channel thereof overlying and vertically spaced from the leading edge of the said member base plate for guiding the entry of said tongue plate into said buckle and for holding it laterally and transversely of said member at the forward end of said member;

a pair of opposed upstanding second side wall flanges on said base plate spaced rearwardly of said guide means; and tongue plate anchoring means including a bar-like member extending between said side wall flanges on each side of said base plate. and extending into said channel and spaced above said base plate, to overly forward side marginal areas of the tongue plate. when the latter is inserted in said buckle, for also holding said tongue plate laterally and transversely of said member.

* a a: s 

1. In a safety buckle for receiving and engaging a tongue plate, the buckle including a non-load bearing housing surrounding a through-load member adapted to be connected at one end to a safety belt strap and having a latch member movable relative to the member for releasably engaging the tongue plate to the member, the member having a base plate and restraint means for laterally and transversely restraining the tongue plate in a plane adjacent and overlying the member base plate, the improvement in through-load member and its associated restraint means comprising the provision of: guide means on said through-load member including opposed side wall flanges on said base plate forming a channel for receiving said tongue plate, each including portions extending into said channel thereof overlying and vertically spaced from the leading edge of the said member base plate for guiding the entry of said tongue plate into said buckle and for holding it laterally and transversely of said member at the forward end of said member; a pair of opposed upstanding second side wall flanges on said base plate spaced rearwardly of said guide means; and a tongue plate anchoring means including a bar-like member extending between said side wall flanges on each side of said base plate, and extending into said channel and spaced above said base plate, to overly forward side marginal areas of the tongue plate, when the latter is inserted in said buckle, for also holding said tongue plate laterally and transversely of said member. 